The circum radius of a triangle whose vertices are $(4,6) ,(0,4)$ and $(6,2)$ is _________ units

Question

$\begin{array}{1 1}(A) \;10\;units\\(B)\;\sqrt {10}\;units \\(C)\;5\sqrt 2 units \\(D)\;2 \sqrt {5}\;units\end{array}$